This invention relates to the processing of molluscs, particularly cephalopods such as squid.
The squid comprises a tapered outer mantle within which are the body organs. The mantle is open at one end and tapers toward a small orifice at the other end, the wings or fins being located on either side of the mantle toward the tapered end, and the head and tentacles protruding from the open end where the mantle is at its widest. A cartiligenous backbone or xe2x80x98penxe2x80x99 on the inside of the mantle provides rigidity and support.
Although squid can be eaten whole, initial preparation for human consumption normally involves removal of the internal organs and separation of the front part of the head and tentacles. The wings and xe2x80x98penxe2x80x99 are also removed as well as the xe2x80x98beakxe2x80x99 or mouth. The tapered mantle may also be turned inside out to assist cleaning, and at some point the squid must be skinned. The edible empty mantle, tentacles, head and wings are then used to make a variety of edible food products.
The present invention is particularly concerned with the initial removal of the internal organs from the mantle i.e. with the gutting of the squid. At present squid are usually gutted by hand, large tough squid with the aid of a hook and small squid using a finger. The resulting partially gutted squid are then turned inside out by pushing the tapered end of the mantle down over a stick or post and then cleaning the remnants from the inside surface of the mantle.
In one alternative gutting process, a pressure-applying roller system forces most but not all of the guts out of the wide end of the mantle tube.
The known processes for gutting and cleaning squid are therefore generally laborious and have low productivity.
According to the present invention there is provided a method of gutting cephalopods, such as squid, wherein the internal organs are contained within an outer mantle open at one end, and wherein the mantle is retained at a fixed distance from a central axis while being rotated about the said axis whereby the internal organs are subjected to a centrifugal force sufficient to eject the organs outwardly through the open end of the mantle.
Preferably the outer mantle is retained by suction in a holding device while being rotated about the central axis. The holding device may comprise an air permeable container or pod disposed in a chamber, the chamber being evacuated such that the mantle is retained by suction in the container or pod when the chamber is rotated about the central axis.
In one embodiment of the invention the chamber comprises a drum and a plurality of containers or pods are angularly spaced around the periphery of the drum. Means are then provided for evacuating the drum while rotating it about the central axis.
In one alternative embodiment, the holding device consists of an open-ended tube or duct shaped at one end to receive the mantle, the other end of the tube or duct communicating with a vacuum device. In this embodiment a plurality of the tubes or ducts may be angularly spaced around the central axis, the inner ends of the tubes or ducts communicating with the vacuum device.